Confined Space:

(This the fifth in a series of safety and health bulletins on specific issues developed/adapted for the GCC by Dan Huziak of Toronto 100M.)

“Are you all right brother?” These were the last words of Robert LaPolice. He called them out to John Hewson, 31, who had climbed down into a Hamilton, Ontario, steel maker’s vacuum degreaser tank to clean it. As Hewson reached the bottom of the tank he collapsed, his lungs filled with argon gas. LaPolice, 26, entered the tank in an attempt to rescue him. In the end, both men died. As a result, Gordon Hewson, 7, Bryant Hewson, 4, and Matthew LaPolice, 8, must face life without their fathers.

A coroner’s inquest into the two fatalities made 30 recommendations including ones which suggested improvements to the steel maker’s confined space entry program and minimum standards regulated by the Ontario government. Unfortunately, any improvements that may result will not benefit LaPolice, Hewson or their families. Nonetheless, both families and area health and safety advocates are working for the implementation of the recommendations. They hold dear the wish that no others suffer as the Hewson and LaPolice families suffer still.

The names may change, but every year workers in many industries work in or around confined spaces, whether they are tunnels, vats, or tankers. All too often, the same scenario is played out – a worker is in trouble, a co-worker goes in to help, and both are killed in the rescue. It is estimated that 60 percent of confined space fatalities occur among rescuers. Too often they are ill equipped and untrained.

 

What is a confined space?

The first step in controlling any hazard comes with its proper recognition. While confined spaces come in many different forms from tanks to trenches, they characteristically have limited routes of entry and exit and they often lack natural ventilation. In addition, their atmospheric conditions can rapidly change without warning. When you combine these characteristics, dangerous conditions can arise for anyone who must work inside the space.

Most legislation defines a confined space as a space in which, because of its construction, location, contents or work activity therein, the accumulation of a hazardous gas, vapor, dust or fume or the creation of an oxygen-deficient atmosphere occurs. Similar standards exist in most states and provinces.

 

How are workers exposed?

Workers in a variety of work environments may encounter confined spaces. These areas are often designed to store a product, enclose materials or processes, or transport substances. As such, they are not usually considered a regular work area. Workers may enter the confined space to perform a specific task such as construction, maintenance, inspection, emergency repairs, or for routine servicing or cleaning. Other workers, however, may work in these spaces almost daily. Those who repair boilers or elevator shafts are two such examples. Some other examples of confined spaces are ink tanks, sewers, silos, furnaces, and septic tanks.

 

What are the potential hazards?

A variety of hazards may exist in the confined space depending on its construction and type of materials being used. It is critical to recognize, assess and control these hazards, especially since conditions can change rapidly.

 

Atmospheric Hazards:

Oxygen Deficiency: Ontario’s Industrial Regulations require acceptable breathing air to contain between 18 percent and 23 percent oxygen. OSHA revised standard, 29 CFR 1910.146 requires acceptable breathing air to contain between 19.5 percent and 23.5 percent oxygen. (See other legislation.)

Oxygen Excess: Oxygen rich environments can cause flammable materials to ignite.

F1ammable Atmospheres: Gases, vapors and dusts can become trapped in confined spaces and create flammable or explosive atmospheres.

Toxic Atmospheres: While they might be safer in other workspaces, some toxic substances – even at low concentrations – can cause health effects in a confined space.

 

Physical hazards:

Entry and Exit: Openings may be small or constricted.

Machinery and Equipment: As in other work settings, unless properly locked out (see Hazards Watch on lockout) machinery and equipment could be inadvertently started up.

Electrical Hazards: Tools that aren’t grounded or properly insulated could cause electrocution and accidental start-ups.

Lines and Systems: If these systems are not properly disconnected and blanked off, they may leak, potentially leaving workers trapped, burned, drowned or smothered.

Walking/Working Surfaces and Visibility: Poor lighting may add to hazards caused by an irregular, sloped, or constricted working surface.

Noise and Vibration: Noise from equipment can be intensified in some confined spaces.

Temperature Extremes and Humidity: Hot and cold temperatures can affect a worker’s ability to perform tasks, while excess humidity can create slippery surfaces.

 

How to assess a confined space

Procedures for working, entering, and exiting safely are crucial and must be tailored to the space itself. A standard program must be developed, but it should be further customized to the hazards found in each particular space. Additional workplace policies and procedures are communicating this hazard information. Any entry program should equally apply for all workers, whether they are regular employees or employed by an outside contractor.

An effective confined space entry program should include the following components.

 

• Identification: The joint health and safety committee should routinely inspect all areas considered to be confined spaces. 
• Inspection and evaluation: Assess for all exiting and potential hazards, including those in adjacent work areas. 
• Site preparation: Clear all debris from the area; bring in equipment only as needed. 
• Isolation-lockout and blanking off procedures: Lock out all energy sources. Disconnect lines and systems, implement lockout procedure. 
• Testing and monitoring: Test for oxygen levels, flammability and toxic materials or possibly a combination of tests. Be sure to conduct stratification monitoring, which tests levels of a substance at various points of the tank or pit. For instance, substances that are heavier than air could pool at the bottom. 
• Purging and ventilation: Remove contaminants by using liquids or non- flammable gases. Introduce gases to make contaminants unreactive. Use proper ventilation sources. 
• Personal protective equipment: Use proper protective equipment, ensure it conforms to standards, and train workers in its use. This equipment should include personal gas monitors. 
• Equipment and tools: Inspect for defects, ensure equipment and tools are insulated and grounded. 
• Attendant and communications: Provide proper training for attendants. Establish a communications system and emergency response procedure. 
• Rescue: Inspect all rescue equipment and provide training in its use. 
• Documented work procedures: Establish procedures for all aspects of confined space work. 
• Entry permits: Effective permits will include a list of identified hazards, safe entry testing, the type of work to be carried out, safe work procedures, necessary protective equipment, and training requirements. Permits will be signed off by a competent confined space supervisor. 
• Training: This must be provided not only to the workers, but also to supervisors, attendants, standby persons and rescue personnel. Training must include rescue drills as well.

 

Additional strategies

Once you have developed a confined space entry program, it must be monitored and adapted as needed to be most effective. Joint health and safety committees in many workplaces have introduced improvements to make confined spaces safer by substituting toxic materials with less hazardous materials; designing newer confined spaces that allow routine maintenance and repairs to be done from outside the space; stationing a fully equipped rescue person outside the confined space, in addition to the attendant; advocating for personal gas monitors; and carrying on continuous monitoring of the environment while workers are inside the confined space.